1. Field of the Invention
The present invention generally relates to illumination control, and more particularly relates to a centrally-controlled intelligent illumination control method, apparatus, and system.
2. Description of the Related Art
In general, a conventional Building Automation System (BAS) includes a subsystem such as an integrated wiring subsystem, a computer-based network subsystem, a security subsystem, a fire control subsystem, and a closed circuit television-based monitoring subsystem. Recently, as economic and technological development matures, the energy conservation of illumination apparatuses and the intelligent management of the illumination apparatuses able to meet the requirements of users have attracted attention. As a result, the illumination control has become more and more important in the field of Building Automation Systems in recent years.
A typical illumination control system includes plural illumination apparatuses, plural illuminance (hereinafter, also called an “illuminance value”) sensors, a central controller, and a communications network. In this kind of illumination control system, when one of the illumination apparatuses emits light according to a dimming level, the corresponding illuminance sensor detects the illuminance value in an area (hereinafter, also called a “lighting area”) where the corresponding illuminance sensor is set and is able to sense the light, then the corresponding illuminance sensor sends the detected illuminance value to the central controller via the communications network, and then the central controller adjusts, on the basis of the difference between the detected illuminance value and a target illuminance value, the dimming level of the corresponding illumination apparatus.
For example, in a paper entitled “Modelling and Simulation of a Lighting Control System” and published in 2011 by Ghent University (Belgium), an illumination control system is disclosed in which a PID controller is utilized for adjusting illuminance. This system may achieve a good illumination control effect under a standard condition. However, when this system is used under a non-standard condition, the response of this system is relatively slow, and the illumination control effect is not good. Furthermore, in this system, it is necessary to adopt plural fixed illuminance sensors for measuring illuminance values. As a result, the number of apparatuses in this system is relatively large, thereby causing the manufacturing cost to be relatively high. Moreover, since the PID controller is designed on the basis of the plural fixed illuminance sensors, this system may only carry out illumination control with respect to fixed positions.
In a paper entitled “An Evolutional Optimization Algorithm to Provide Individual Illuminance in Workplaces”, written by Shingo Tanaka, et al. of Doshisha University (Japan), and published in 2009, an illumination control system is disclosed which is on the basis of a movable illuminance sensor. In this system, a distributed control algorithm is adopted. Furthermore, only when a current illuminance value is less than a target illuminance value, this system starts working. This may result in a stroboscopic problem. Moreover, since the movable illuminance sensor is adopted in this system for carrying out measurement, a user may feel inconvenienced when he wants to move this kind of illuminance sensor from a place to another place.
In addition, in Japanese Patent Application Publication No. 2009-238529, an illuminance control system is disclosed. In this system, a portable device is employed for measuring an illuminance value and for sending positional information, and a control device receives the positional information and controls, on the basis of the received positional information, a nearby illumination apparatus. However, this system may only control the on-off switching of the illumination apparatus; that is to say, this system may not adjust a dimming level of the illumination apparatus according to a desired dimming level (i.e., a target dimming level). Moreover, since this system utilizes the portable device for measuring the illuminance value, a user may also feel inconvenienced when he wants to move this kind of device from a place to another place.
Therefore, it is necessary to provide an illumination control system in which an illuminance sensor is not necessary, and by using this kind of illumination control system, it is possible to carry out intelligent illumination control with respect to a predetermined lighting area so as to be able to satisfy the requirements of users, to decrease the energy consumption, and to reduce the manufacturing cost.